Been a while since I read it so I went and found it. trietnguyen was right, I had it backwards, my apologies. My question would still stand, although it does look like pitches are "used" independently and not weighted by the answer. So taking two pitchers each with 5 pitches weighted to an average pitch rating of, say, 75, they may not produce equally, depending on where the ratings fall in the P#. Under this answer you would want to look for P1 with the highest rating, P2 next and so on.
So there isnt much of a difference between an 80/60/70 pitcher and a 70/80/60? ( - All-Star - 2:25 PM)
Generally, a pitcher's first pitch is considered his out pitch, his second pitch is used to set up his out pitch and the other pitches are off speed or off balance pitches. That is the way the engine views them, so in your example there is a difference between the two pitchers.